The present invention relates to a run-in trough system (High Speed Delivery System) for a cooling bed that stops steel bars formed in a prescribed shape by the rolls of the final finishing stand by hot rolling equipment in a prescribed position and then transferred onto a cooling bed for the subsequent process without having any steel jump out from the run-in trough or experience deformation.
In the production of steel bars by means of hot rolling equipment, ingots, or billets, of uniform unit weight must be used as material for effectively manufacturing high-accuracy steel bar products having a specified diameter and length with little loss. However, it is practically impossible to have all ingots or billets uniform in weight and, in any case, the final cut pieces are not uniform in length.
As a result, in a conventional run-in trough system, it is difficult to stop steel bars at any predetermined position without having any jump out from the run-in trough or deformation, because the steel bars formed in a prescribed shape by the rolls of the final finishing stand of hot rolling equipment and sent out onto the cooling bed have different inertia depending on their shape, i.e. their diameter or length. For that reason, it has been a normal practice to have some margin in the length of the run-in trough. But this had the problem of requiring larger sizes for both the equipment and the factory building, therefore, leading to a bigger investment.
Moreover, there was also the problem of a drop in working efficiency because the top ends of the steel bars were not aligned if they couldn't be stopped at a prescribed position on the run-in trough, and had to be aligned in the subsequent process.
To solve the problems of the conventional run-in trough system, the applicant of the present invention previously proposed a run-in trough system for cooling bed for transferring hot rolled steel bars to cooling beds constructed by splitting the run-in trough into a plural number of parts in the direction of steel bar length. The parts were arranged swingably in a vertical direction on a fixed shaft provided on the main body of the run-in trough. A open trough received steel bars supplied onto the run-in trough in a state in contact with a closing plate at the upper position and discharged the steel bars at the lower position, the open trough having a driving device. An inclined chute is higher than the open trough when the open trough is in the lower position and at a distance sufficient to enable passage of the open trough moving in a vertical direction. Steel bars were received when the open trough moves downward and transfers the received steel bars to the cooling bed, and the system was provided with a device for stopping the steel bars supplied onto the run-in trough (refer to European Patent No. 331340). However, this apparatus had the problem of requiring a complicated equipment structure because the device for stopping the steel bars supplied to the run-in trough was provided in disregard of the open trough of the run-in trough.